> Yesterday, using v0, I replicated a full nextjs UI copying a major saas player

Yeah its over for them. Complicated business logic and sprawling systems are what are keeping backend safe for now. But the big front end code bases where individual files (like react components) are largely decoupled from the rest of the code base is why front end is completely cooked

I have a medium-sized typescript personal project I work on. It probably has 20k LOC of well organized typescript (react frontend, express backend). I also have somewhat comprehensive docs and cursor project rules. In general I use Cursor in manual mode asking it to make very well scoped small changes (e.g. “write this function that does this in this exact spot”). Yesterday I needed to make a largely mechanical change (change a concept in the front end, make updates to the corresponding endpoints, update the data access methods, update the database schema). This is something very easy I would expect a junior developer to be able to accomplish. It is simple, largely mechanical, but touches a lot of files. Cursor agent mode puked all over itself using Gemini 2.5. It could summarize what changes would need to be made, but it was totally incapable of making the changes. It would add weird ha…